ANS-C01 Question 377
Select 3You are troubleshooting intermittent packet loss and latency issues in a multi-VPC architecture connected via AWS Transit Gateway. To diagnose the root cause and assess network performance, which combination of logs and metrics should you analyze?
- A
Amazon CloudWatch metrics for Transit Gateway Data Transfer metrics (BytesIn/BytesOut and PacketDropCount)
- B
VPC Flow Logs to analyze traffic patterns and determine dropped packets at the VPC level
- C
AWS CloudTrail logs to track API calls related to network configuration changes
- D
Amazon Route 53 query logs to analyze DNS resolution issues
- E
AWS Transit Gateway Flow Logs to trace packet flow across the Transit Gateway
Show answer and explanation
Correct answers: A, B, E
Explanation
To diagnose network performance and reachability issues like packet loss in a multi-VPC architecture using AWS Transit Gateway, you need to analyze data from multiple sources. CloudWatch metrics for Transit Gateway provide high-level insights into traffic throughput and packet drops. VPC Flow Logs enable you to analyze traffic patterns and dropped packets within individual VPCs. Transit Gateway Flow Logs allow for tracing and understanding traffic flow across the Transit Gateway itself. Together, these logs and metrics provide a comprehensive view of network performance and help identify the root cause of issues.
- A. Correct.
Transit Gateway Data Transfer metrics in CloudWatch, such as BytesIn/BytesOut and PacketDropCount, provide insight into traffic volume and packet loss at the Transit Gateway level. This is crucial for diagnosing performance issues in a Transit Gateway architecture.
- B. Correct.
VPC Flow Logs allow you to capture information about the IP traffic going to and from network interfaces in your VPC. They are essential for identifying dropped packets and traffic patterns at the VPC level.
- C. Incorrect.
CloudTrail logs are useful for auditing API calls and tracking changes in network configurations, but they do not provide metrics or packet-level insights for diagnosing performance or reachability issues.
- D. Incorrect.
Route 53 query logs are specific to DNS requests and are not directly useful for analyzing packet loss or network performance issues in a multi-VPC architecture.
- E. Correct.
Transit Gateway Flow Logs allow you to capture metadata about the traffic flowing through the Transit Gateway, such as source and destination IP addresses, ports, and protocols. These logs are critical for tracing packet flow across the Transit Gateway and identifying potential bottlenecks.